Apparatus for mounting rotary drums

ABSTRACT

A journal for cantilevered mounting of a rotary drum comprising a double acting thrust rolling bearing located in a single housing.

United States Patent 1191 Schiirger et a1.

[ 1 Aug. 20, 1974 APPARATUS FOR MOUNTING ROTARY DRUMS [75] Inventors: Rainer Schiirger, Arnstein; Lothar Walter, Schweinfurt; Manfred Brandenstein, Aschfeld; Giinter Neder, Schweinfurt, all of Germany [73] Assignee: SKF Industrial Trading and Development Company B.V., Amsterdam, Netherlands [22] Filed: Feb. 9, 1973 [21] Appl. No.1 331,112

[30] Foreign Application Priority Data Feb. 17, 1972 Germany 7205916 [52] US. Cl. 308/230 [51] Int. Cl. F16C 17/06 [58] Field ofSearcli 308/230-234; 68/140 [56] References Cited UNITED STATES PATENTS 2,963,892 12/1960 Edwards 68/140 3,080,199 3/1963 Rickley 308/234 3,613,406 10/1971 Toth 68/140 FOREIGN PATENTS OR APPLICATIONS 6,711,687 8/1967 Netherlands 68/140 Primary Examiner-Charles J. Myhre Assistant Examiner-Frank Susko Attorney, Agent, or FirmMurray Schaffer [57] ABSTRACT A journal for cantilevered mounting of a rotary drum comprising a double acting thrust rolling bearing located in a single housing.

8 Claims, 4 Drawing Figures 1 APPARATUS FOR MOUNTING ROTARY DRUMS BACKGROUND OF INVENTION The present invention relates to apparatus for the cantilevered mounting of rotary drums and in particular to apparatus for rotatably journalling the drums of washing, spinning, or drying machines.

In general, the drum or basket of a washing machine is mounted at the end of a centralaxially extending shaft which is journalled in a roller bearing usually comprising two rows of roller elements axially arranged one behind the other. In the known constructions the bearing has a relatively large axial extent, since both rows of roller elements must be spaced a large distance vfrom each other, so that the turning moment of the cantilevered device can be absorbed. Often the assembly area in the axial direction is so limited that the well known and standard axial bearings can not be used. On the other hand, more than sufficient room is available in the radial direction.

It is the object of the present invention to provide apparatus for journalling the drum or basket of rotary machines of the type described which overcomes the prior art.

It is an object of the present invention to provide apparatus for mounting rotary drums which is relatively economical of space in the axial direction without having any loss of bearing capacity.

These objects as well as others together with other advantages of the present invention are set forth in the following disclosure.

SUMMARY OF THE INVENTION According to the present invention apparatus for mounting in cantilevered fashion the rotary drum or basket of awashing, spinning or drying machine is provided which comprises a journal having a double thrust rolling bearing located in a single housing. Preferably the bearing comprises two axially spaced rows of rolling elements which have at least one common race structure so that the bearing has double working sides in the axial direction.

The apparatus according to the present invention can be built as a unitary structure which can be easily and quickly installed on and disassembled from the machine. Because of the two sided axial working construction a rolling bearing journal of the present invention can absorb relatively high loads while simultaneously requiring very little space in the body of the machine itself.

A further advantage of the present invention lies in the fact that increased radial loads may also be absorbed. This may be accomplished by providing the outer periphery of the common race structure with a radial rolling bearing acting against the housing structure.

Still a further advantage may be obtained from the present invention. The housing may be formed in one or several pieces of sheet metal material which in assembled form provides an enclosed bushing which may be easily installed within the journal block of the machine. Preferably the bushing housing and the machine block are provided with interlocking and interengaging securing means, such as a bayonet type latch, so that installation and disassembly can be made without tools. A particular advantage of this construction lies in the fact that repairs and reconstruction can be made with ease and without excessive costs.

Full details of the present invention follow herein and may be seen in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. la is a sectional view taken in a radial plane above the center line of anapparatus embodying the present invention; H

FIG. 1b is a view similar to that of FIG. 1a taken below the center line and showing a modification of the apparatus;

FIG. 2 is a view similar to that of FIG. 1a showing another embodiment; and

FIG. 3 is yet another view similar to FIG. la of still another embodiment. I

DESCRIPTION OF INVENTION As seen in FIG. 1 an axial rolling bearing generally depicted by numeral 1 is provided with two rows of rolling elements 2 having a common race disk 3 located between them and a pair of outer race disks 4. A spacer ring 5 is arranged between the two enclosing disks 4. The enclosing disks 4 are held together and compressed against the spacer 5 by an annular bushing 6 which is formed from two pieces of sheet metal, welded or otherwise fastened together.

The output side of the bushing 6 is provided with a radially outwardly directed flange 7, which has at its outer circumference an axial directed shoulder. The flange 7 is provided with a plurality of slots or openings 7 arranged about its periphery, as seen in FIG. 1b. A housing 9 forming an annular recess in the machine for the bearing is provided. The housing has a stepped inner side which surrounds the bushing 6'and engages the circumference thereof. The housing 9 has .a plurality of bent tongues 8 which correspond vin number to the openings 7. In assembling the bearing, .the bushing 6 is inserted into the housing 9 from the right, as seen in the drawing, so that the inclined tongues 8 of the housing 9 facilitate the shoving of the flange 7 into the housing 9. Thereafter the bushing 6 is turned radially about its center so that the axial shoulders of the flanges 7 grip beneath the steps of the housing 9. In this manner a secure binding of the bushing and flange is effected, in the manner similar to a bayonet type latch, and one which does not require tools to effect.

The common race disk 3 is secured by a screw bolt 10 to the rear face of a shaft 11 on the front end of which the hub 12 of the drum is pressed or forced fit. The common race disk 3 is provided with a circumferential groove about its outer peripheral edge in which a row of rolling elements 13 held in a cage, is mounted. The rolling elements 13 bear against the inner surface of the spacer 5 and thus provide a radial bearing for the disk 3.

The output side of the bushing is sealed by a slide packing 14 comprising a first slide ring 15 which is held within the bushing 6 and a second slide ring 16 against which the first ring 15 abuts. The second slide ring 16 is held against both the face of the hub 12 and the surface of shaft 11.

The variant shown in FIG. 1b provides another way of mounting the drum to the bearing. In this case the drum is not force fit on the shaft 11 but is instead formed of a hollow shaft 17 which is welded or otherwise secured to common race disk 3 and which extends more or less freely through the hub 12. Within the hollow shaft 17 are arranged two pairs of annular plate springs 18, such as Belleville springs, having their concave sides facing each other and their edges engaging the inner surface of the shaft 17. A spacer block 19 is axially arranged between the two pair of springs 18. Coaxial of the shaft 17 and within the plate springs there are arranged two oppositely facing stepped rings 20. The springs 18 and rings 20 are arranged so that the edges of each of the pairs of springs lie against the corresponding steps of the rings, but the rings have a generally opposite and outward inclination. The rings are held together by one or more screws or bolts 21 and are correspondingly threaded so that when the bolt 21 is tightened the rings 20 are drawn together axially. Thus, when the screws are tightened the pairs of springs 18 are squeezed together causing them to exert a resilient radial force outwardly, consequently creating a pressure on the hollow shaft 17 which tightens it against the hub 12 in a secure fastening.

In the embodiment of FIG. 2 the double thrust rolling bearing 1 is a double row angular contact ball bearing. The common race disk 3 is provided with circumferential race grooves at its two peripheral edges, while a pair of opposed race rings 31 are arranged within the outer corners of the bushing 6. In this arrangement the angular contact bearings provide a theoretically large bearing distance L between the two rows, which thus enables the absorption of relatively large load or turning moments. In addition this arrangement also permits the asorption of relatively large radial loads, so that the radial row of bearing rollers about the peripheral edge of the disk 3 (FIG. 1) will not be necessary.

In FIG. 2, the mounting of the drum about a hollow shaft 17 is again illustrated, however, here the shaft 17 is fastened by the use of bolts 32 to a driving member 33, as for instance a belt pulley.

In the embodiment of FIG. 3 the double thrust rolling bearing 1 is formed by the use of a double row of conical rolling elements 34 seen in the figure which are arranged between a pair of spaced inclined race blocks 3' and a central common double inclined faced race block 4'. The incline of the race blocks 3' and 4' is such that the axis of rotation of the rollers lie along axes which intersect substantially along the axis of rotation of the drum and the force vectors of the rollers extend along lines which move axially outward to have a theoretical bearing distance L of relatively extreme length. The common race block 4 is mounted to seat against the bushing 6, which in this embodiment is formed of two parts which telescope together. The block 4' is held in fixed position between a first head 22 formed on the interior section of bushing 6 and a second head 22' formed on the outer section of the bushing 6. The two blocks 3' are spaced by a spacer and are axially squeezed together by a block 35 which is fastened by a bolt 36 screwed into the outer face of solid shaft 11. A C-ring clamp 37 or the like, seated in a circumferential groove in the shaft 11, acts as an abutment stop for the inner block 3'.

Each of the embodiments shown provide an improved cantilevered journal apparatus for a rotary drum such as used in washing machines, clothes driers and the like. The axial radial bearing for this construction requires very little axial room for assembly and provides a very compact unitized bearing which is economical to produce and to install, as well as to remove and replace. Particularly economical is the bayonet type arrangement by which the bearing unit can be secured to the annular machine bearing block itself.

It will be observed further that the single radial face structure flanked on both sides by rolling elements comprises a double thrust rolling bearing of small dimension and strong load capacity. The choice of angles for the inclined races, can be made to obtainthe maximum benefit for the particular use.

Various modifications have been shown. Other modifications and changes will be apparent to those skilled in this art. Accordingly, it is intended that the present disclosure be taken as illustrative only and not limiting of the present invention.

What is claimed:

1. In a centrifugal rotary cantilevered drum machine such as for washing or drying the combination comprising a drum, an axial shaft secured to one end of said drum and extending outwardly therefrom along a subwithin said bushing about said shaft, said two rows of rolling elements having a common race member located therebetween and a pair of exterior race members engaging each of said rows respectively, to define a fixed theoretical bearing distance between the two rowsof rolling elements which is substantially greater than the axial distance between said rows of rolling elements.

2. The apparatus according to claim 1 wherein said common race member is provided with a radial bearing arranged between the peripheral edge thereof and said bushing.

3. The apparatus according to claim 2 wherein axial slide packing means isarranged between the housing and the rotary drum.

4. The apparatus according to claim 1 wherein the axial shaft is hollow and extends through an annular hub in said drum, said shaft having pressure fasteners for compressing the shaft against the hub comprising a pair of annular plate springs, a pair of annular slide members in which said rings are held and means for ad justable moving said slide members together to press said annular springs against the inner surface of said shaft.

5. The apparatus according to claim 1 wherein the bushing is set within an annular opening of the housing, said bushing and said opening being provided with cooperating interlocking means whereby said bushing may be disengageably secured in said opening.

6. The apparatus according to claim 5 wherein the bushing is provided with a radially outward flange having a plurality of bent slots about its periphery, and the opening is provided with an inner periphery having a plurality of openings, each of which including a bent tongue corresponding to the number of and spacing between said slots, said slots and tongues cooperating to lock together on rotation of said bushing.

7. The apparatus according to claim 1 wherein said common race is secured to the axial shaft and said pair of races are secured to the bushing.

8. The apparatus according to claim 1 wherein said common race is secured to said bushing and said pair of races are secured to said axial shaft. 

1. In a centrifugal rotary cantilevered drum machine such as for washing or drying the combination comprising a drum, an axial shaft secured to one end of said drum and extending outwardly therefrom along a substantially horizontal line, a supporting housing surrounding said extending shaft, and a double thrust rolling bearing interposed between said shaft and housing, said thrust bearing coMprising a bushing fastened to said housing, two rows of rolling elements mounted within said bushing about said shaft, said two rows of rolling elements having a common race member located therebetween and a pair of exterior race members engaging each of said rows respectively, to define a fixed theoretical bearing distance between the two rows of rolling elements which is substantially greater than the axial distance between said rows of rolling elements.
 2. The apparatus according to claim 1 wherein said common race member is provided with a radial bearing arranged between the peripheral edge thereof and said bushing.
 3. The apparatus according to claim 2 wherein axial slide packing means is arranged between the housing and the rotary drum.
 4. The apparatus according to claim 1 wherein the axial shaft is hollow and extends through an annular hub in said drum, said shaft having pressure fasteners for compressing the shaft against the hub comprising a pair of annular plate springs, a pair of annular slide members in which said rings are held and means for adjustable moving said slide members together to press said annular springs against the inner surface of said shaft.
 5. The apparatus according to claim 1 wherein the bushing is set within an annular opening of the housing, said bushing and said opening being provided with cooperating interlocking means whereby said bushing may be disengageably secured in said opening.
 6. The apparatus according to claim 5 wherein the bushing is provided with a radially outward flange having a plurality of bent slots about its periphery, and the opening is provided with an inner periphery having a plurality of openings, each of which including a bent tongue corresponding to the number of and spacing between said slots, said slots and tongues cooperating to lock together on rotation of said bushing.
 7. The apparatus according to claim 1 wherein said common race is secured to the axial shaft and said pair of races are secured to the bushing.
 8. The apparatus according to claim 1 wherein said common race is secured to said bushing and said pair of races are secured to said axial shaft. 